By using the orthogonal test methodology, highspeed milling experiments of 3Cr2Mo mold steel were performed. The forecasting model of cutter wear and surface roughness were established. On this basis, the optimization model was established based on the maximum production efficiency and the minimum production cost. Using the multiobjective optimization methodology in Matlab, which based on the NSGAⅡ algorithmto solve it, and get the better milling parameters.